6541644165 has 32 divisors (see below), whose sum is σ = 12053200896. Its totient is φ = 2967631680.

The previous prime is 6541644163. The next prime is 6541644167. The reversal of 6541644165 is 5614461456.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (6541644163) and next prime (6541644167).

It is not a de Polignac number, because 6541644165 - 2¹ = 6541644163 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6541644163) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 224037 + ... + 251546.

It is an arithmetic number, because the mean of its divisors is an integer number (376662528).

Almost surely, 2^6541644165 is an apocalyptic number.

It is an amenable number.

6541644165 is a deficient number, since it is larger than the sum of its proper divisors (5511556731).

6541644165 is a wasteful number, since it uses less digits than its factorization.

6541644165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 475729.

The product of its digits is 345600, while the sum is 42.

The square root of 6541644165 is about 80880.4312859421. The cubic root of 6541644165 is about 1870.2326690584.

The spelling of 6541644165 in words is "six billion, five hundred forty-one million, six hundred forty-four thousand, one hundred sixty-five".